Interesting Aveline, and confirms my view that like many conditions, there's a combination of factors.
My mum was the only one who got osteo-arthritis, and her sport was swimming (so not much strain on joints)
My aunt was a cyclist, not much strain on the whole, though some of her club members have had knee problems. She is the only one still alive, very fit & active in her late 80s, although she no longer cycles.
My mum's friend was a runner (almost made the 1948 Olympics) so you would have thought a lot of strain on joints, but she never had any problems. I did ask her about training, and in those days it was mainly on grass.
I, like my mum, was a swimmer and have osteo-arthritis.
I suspect that you have some pre-disposition and some wear and tear from your youth. Good luck with your new hip!